There are currently in use electric cables constituted by a bundle of carbon fibres enveloped in a sheath provided by an electrically insulating material, for example a silicon resin; since the carbon has an elevated resistance to heat, such carbon fibre cables have an optimal application as heating electrical resistors, for example in the area of thermocouples.
In order to provide the electrical current to such carbon fibre cables, they must be connected, at their ends, to metallic conductors, typically made of copper or aluminium, connected, directly or by means of appropriate circuits, to a power source.
It is known to provide the electrical connection between one end of the carbon fibre bundle to one end of the metallic conductor by means of a connection method, known as “crimping”, that provides for the insertion of the two ends in an appropriate metallic ring, that is then pressed so as to press therein the carbon fibres and the metallic conductor, providing the electrical contact therebetween.
Such known connection method has however a great drawback: due to the very reduced mechanical resistance, in particular of tensile resistance, of the carbon fibres, only modest mechanical stresses on one or both of the cables may cause the breakage of such carbon fibres, with the consequent interruption of the electrical connection between the two cables.
In order to limit the possibility of rupture of the carbon fibres, the compression of the metallic ring should not be too elevated, which however compromises the quality of the electrical contact between the metallic conductor and the carbon fibres.
Moreover, it is not possible to connect a metallic conductor to a bundle of carbon fibres by means of soldering, since the carbon, due to its physical/chemical properties, is not adapted to be soldered.
Due to the above-mentioned drawbacks the use of such carbon fibre cables is therefore very reduced.